Processing method

Abstract

A method for treating a pyrite-containing slurry is disclosed. The method includes removing pyrite from the pyrite-containing slurry and forming (i) an inert stream and (ii) a pyrite-containing material, the pyrite-containing slurry including tailings from a tailings dam or ore processing plant. The method also includes leaching the metal-sulfide-containing material and the pyrite-containing material with a leach solution and microorganisms. A method for leaching the metal-sulfide-containing material is also disclosed. A flotation circuit for an ore processing plant for metal-sulfide-containing material is also disclosed.

Description

[Technical Field]

[0001] The present invention relates, for example, to a method for processing pyrite-containing slurry by beneficiation.

[0002] The present invention relates, in particular, to a method of processing a pyrite-containing slurry by, for example, beneficiating the slurry to remove pyrite, and then using the removed pyrite in a downstream method step.

[0003] The present invention relates, in particular, to a method of processing a pyrite-containing slurry in the form of tailings from a processing plant for recovering metals from metal sulfide-containing materials such as metal sulfide minerals, by removing pyrite from the tailings, and using the removed pyrite in a downstream method step, although this method is not exclusive.

[0004] A specific application of the present invention is the removal of pyrite from pyrite-containing slurries from tailings dams or processing plants for recovering copper from copper sulfide-containing materials such as copper sulfide minerals.

[0005] A particular application of the present invention is to use the removed pyrite in a downstream method step to recover valuable metals such as copper from metal sulfide-containing materials such as metal sulfide minerals such as copper sulfide minerals.

[0006] The present invention also relates to a deposition leaching method characterized by leaching a deposition of aggregates containing metal sulfide-containing materials, such as metal-containing sulfide minerals like copper sulfide minerals, wherein the aggregates are generated at least partially from pyrite-containing materials in order to recover valuable metals from the sulfide-containing materials.

[0007] The present invention also relates to a deposit characterized by a deposit comprising aggregates containing metal sulfide-containing materials, such as metal sulfide minerals, such as copper sulfide minerals, which are at least partially formed from pyrite-containing materials.

[0008] The present invention also relates to a flotation circuit for an ore processing plant for metal sulfide-containing materials.

[0009] The present invention also relates to an ore processing plant for metal sulfide-containing materials. [Background technology]

[0010] The aforementioned technical field of the present invention relates to the production of metals such as copper, nickel, zinc, or cobalt from metal sulfide-containing materials, such as metal sulfide minerals in mined materials.

[0011] The term “mined material” should be understood herein to include material that has been mined and is being transported from a mine to (a) downstream processing operations for the direct recovery of metals from the material, or (b) storage.

[0012] The following description of the present invention focuses on copper as an example of a metal, which is found in copper sulfide-containing materials such as copper sulfide minerals.

[0013] Copper is an increasingly important metal for the transition to a low-carbon global economy.

[0014] Current wet processing plants for recovering copper from copper sulfide-containing materials such as copper sulfide ores and concentrates, such as those including flotation circuits, typically produce large quantities of tailings in the form of an aqueous slurry of particles, which is usually fine powder, but may also contain coarse particles with low concentrations of copper in copper sulfide-containing materials such as copper sulfide minerals.

[0015] The following description of tailings relates to (a) tailings in tailings dams that store tailings from ore processing plants, or (b) tailings directly from tailings streams of ore processing plants for copper sulfide-containing materials, such as copper sulfide-containing ores containing copper sulfide minerals.

[0016] The tailings are typically stored in dams. Typically, the dams are quite large, and their capacity increases as mining continues.

[0017] Tailings and tailings dams often pose significant environmental and safety risks during the life of a mine.

[0018] Maintaining tailings dams throughout the life of a mine and rehabilitating them at the end of the mine's life pose significant problems. Suspended solids take time to settle to facilitate the safe disposal of materials, often a significant amount of time. Additionally, there are potential problems with the structural integrity of tailings dams. There are known dewatering techniques to reduce the volume of tailings, but these add cost and complexity to the mining operation.

[0019] Occasionally, there are catastrophic failures of tailings dams, which have caused loss of life and significant damage in areas downstream of the dams.

[0020] There are also concerns regarding mines taking steps to ensure the structural integrity of dam walls to minimize the risk of failure.

[0021] Tailings also often contain contaminants, either directly or through reactions, which present challenges for mine rehabilitation.

[0022] For example, tailings often contain significant concentrations of pyrite, which can pose potential environmental risks as the tailings oxidize and generate acidic effluents that require treatment, such as by neutralizing the acidity, before the tailings can be discharged.

[0023] It is important to note that contaminant removal is not a solution if the cost is prohibitive and / or the contaminants remain as contaminants in another medium that must be stored / contained in some way once removed from the tailings.

[0024] Therefore, contaminants such as pyrite add complexity to tailings treatment.

[0025] The present invention provides a method that enables the beneficial treatment of pyrite-containing tailings.

[0026] The above and following descriptions focus on tailings from a wet treatment plant for copper-containing ores. The present invention also extends to tailings resulting from the treatment of ores containing other metals such as cobalt, nickel, and zinc.

[0027] The above description is not an endorsement of common general knowledge in Australia or elsewhere. Summary of the Invention

[0028] The present invention involves removing pyrite from a pyrite-containing slurry such as tailings dams for metal sulfide-containing materials like metal sulfide-containing ores containing metal sulfide minerals or pyrite-containing tailings from an ore treatment plant, and using the pyrite to contribute to the removal of metals such as copper, nickel, zinc, or cobalt from the metal sulfide-containing materials by utilizing the acid and exothermic capabilities of pyrite. Therefore, it is based on the recognition that the environmental impact of pyrite is also reduced.

[0029] One particular application of the present invention that the applicant has recognized and is of interest to the applicant is well-suited for the use of pyrite removed from pyrite-containing tailings and is the application of heap leaching for mined materials containing metals such as copper, nickel, zinc, or cobalt. The applicant has found in the present application that pyrite can be beneficially used, for example, in aggregates of mined materials and pyrite, and then formed in a heap and leached by leachate and microorganisms. Although this may overlap with other descriptions, the various aspects of the present invention are as follows. However, the present invention is not limited to the following. [1] A method for processing pyrite-containing slurry, (a) a step of removing pyrite from the pyrite-containing slurry to form (i) an inert flow and (ii) a pyrite-containing material, wherein the pyrite-containing slurry includes tailings from a tailings dam or ore processing plant, (b) A step of leaching the metal sulfide-containing material and the pyrite-containing material with a leachate and microorganisms to remove the metal from the metal sulfide-containing material and form a metal-containing leachate, wherein the pyrite in the pyrite-containing material generates an acid and heat that promotes the leaching of the metal from the metal sulfide-containing material, and the microorganisms oxidize ferrous to ferric, A method that includes this. [2] The method according to [1], wherein the pyrite removal step (a) comprises the steps of (i) suspending the pyrite-containing material in the pyrite-containing slurry, and (ii) generating the inert flow as one flotation product, and (ii) generating the pyrite-containing material as another flotation product. [3] The method according to [2], wherein, prior to the flotation step, the pyrite removal step (a) includes a size separation step via a cyclone or other suitable sorting device, the size separation step separates larger particles in the pyrite-containing material from the remaining pyrite-containing slurry, and the remaining pyrite-containing slurry is transferred to the flotation step. [4] The method according to [3], wherein the pyrite removal step (a) includes the steps of reducing the size of the larger particles in the pyrite-containing material within a size reduction circuit, and returning the reduced-size particles to the size separation step. [5] The method according to [3] or [4], wherein the pyrite removal step (a) includes the step of selecting the operating conditions such that the pyrite particles in the pyrite-containing material in the remaining pyrite-containing slurry have the particle size distribution required for the downstream leaching step (b). [6] The pyrite particles in the pyrite-containing material have a P value of 1 mm or less than 1 mm. 80 A method according to any one of [1] to [5], having a particle size of [1]. [7] The pyrite particles in the pyrite-containing material have a P value of 250 μm or less than 250 μm. 80 A method according to any one of [1] to [6], having a particle size value of . [8] The method according to any one of [1] to [7], wherein the pyrite removal step (a) comprises the steps of thickening and / or filtering the pyrite-containing material and forming a pyrite-containing concentrate. [9] The method according to any one of [1] to [8], comprising the step of using the inert flow as a water source in a treatment plant for recovering metal from the metal sulfide-containing material.

[10] The method according to any one of [1] to [9], wherein the metal is copper and the metal sulfide-containing material is a copper sulfide mineral.

[11] The method according to

[10] , wherein pyrite is 1 to 10% by weight of the total mass of the copper sulfide-containing material and the pyrite-containing material.

[12] The method according to any one of [1] to

[11] , further comprising the step of mixing the metal sulfide-containing material and the pyrite-containing material prior to the leaching step (b).

[13] The aforementioned leaching step (b) is, i. A step of agglomerating metal sulfide-containing materials such as pyrite-containing materials and copper sulfide-containing materials to form aggregates, ii. A step of depositing and leaching metals such as copper from the aggregate to produce a noble liquid leachate containing metals such as copper in a solution, iii. A step of recovering metals such as copper from the leached noble liquid, The method described in

[12] , including the method described in

[12] .

[14] A deposition leaching method for mined materials containing metals such as copper, nickel, zinc, or cobalt in a metal sulfide-containing material, (a) (i) tailings containing material produced from pyrite-containing tailings from a tailings dam or ore processing plant, and (ii) mined material such as waste rock, the step of leaching the deposit of aggregates produced from the tailings using a leachate and microorganisms, wherein the tailings in the tailings containing material generate acid and heat to facilitate the leaching of metals from the mined material, and the microorganisms oxidize ferrous iron to ferric iron, (b) A step of collecting a noble liquid leachate containing the metal in a solution from the deposit, A method characterized by the following.

[15] A deposit that leaches metals such as copper, nickel, zinc, or cobalt from metal sulfide-containing materials in mined materials, (a)(i) Pyrite-containing material generated from pyrite-containing tailings from tailings dams or ore processing plants, and (ii) Deposition of aggregates generated from mined materials such as waste rock, (b) (i) supplying leachate and microorganisms to the deposit so that the leachate flows downward through the deposit and leaches the metal from the mined material, and (ii) collecting the leachate containing the metal in solution from the deposit, the pyrite generating acid and heat in the deposit to facilitate the leaching of the metal from the mined material, and the microorganisms oxidizing ferrous to ferric, A deposit containing this material.

[16] The deposit described in

[15] , wherein pyrite accounts for 1 to 10% by weight of the total mass of the aggregate.

[17] A flotation circuit for an ore processing plant for metal sulfide-containing materials, (a) A pulverizer feed flotation circuit for generating tailings and concentrate from a pulverizer feed, wherein the tailings include a metal sulfide-containing material slurry, (b) A pyrite flotation circuit for generating pyrite concentrate and tailings, Flotation circuit.

[18] The pyrite flotation circuit according to

[18] , wherein the pyrite flotation circuit is configured to process the pyrite concentrate stream according to a method for processing the pyrite-containing slurry described in any of [1] to

[13] .

[19] The flotation circuit according to

[17] or

[18] , wherein the crusher feed flotation circuit includes a coarse separator / capture cell and a bulk cleaner cell, wherein the coarse separator / capture cell and the bulk cleaner cell are configured to (i) process the crusher feed and generate a first tailings stream and a concentrate stream, and (ii) process the concentrate stream and generate a second tailings stream and another concentrate stream, and transfer the other concentrate stream and the second tailings stream to the pyrite flotation circuit for further processing in the circuit, such as metal recovery.

[0030] As stated above, the term “mined material” should be understood herein to include material that has been mined and transported from the mine to (a) downstream processing operations for the direct recovery of metals from the material, or (b) to a stockpile for subsequent processing.

[0031] Therefore, the present invention is more than just removing pyrite from a single waste stream, namely pyrite-containing slurry. The present invention does this and thus improves the pyrite-containing slurry from an environmental standpoint. However, the present invention also allows for the beneficial use of pyrite in downstream processes and processes the pyrite removed from the slurry in a manner that reduces the net environmental impact of the pyrite.

[0032] In a broad sense, the present invention is a method for removing copper from a low-grade copper-containing material having copper sulfide minerals, (a) A step of obtaining pyrite-containing slurry from a tailings dam or tailings flow of an ore processing plant, (b) a step of removing pyrite from pyrite-containing slurry by suspending the pyrite-containing material and forming (i) an inert flow and (ii) a flow containing the pyrite-containing material, (c) A step of mixing a low-grade copper-containing material having copper sulfide minerals with a pyrite-containing material, (d) A step of extracting copper from a copper-containing material using an leachate and microorganisms, Includes, The pyrite in pyrite-containing materials generates acid and heat that facilitates the leaching of copper from copper-containing materials. The present invention provides a method for oxidizing ferrous iron to ferric iron using microorganisms.

[0033] The step of removing pyrite from the pyrite-containing slurry may include selecting operating conditions such that the pyrite particles have the particle size distribution required for the leaching step (d).

[0034] The step of removing pyrite from a pyrite-containing slurry may include the steps of separating larger particles of the pyrite-containing material from the remaining pyrite-containing slurry, reducing the size of the larger particles using a size reduction circuit, and returning the reduced-size particles to the size separation step.

[0035] In a broad sense, the present invention is (a) The step of removing pyrite from pyrite-containing slurry to form an inert flow and pyrite-containing material as described herein, (b) A method for processing a pyrite-containing slurry is provided, comprising the step of using a pyrite-containing material in a downstream leaching step in which pyrite in the pyrite-containing material generates acid and heat that facilitates the leaching of metals such as copper, nickel, zinc, or cobalt from a metal sulfide-containing material such as mined material such as ore.

[0036] More specifically, the present invention relates to a method for processing pyrite-containing slurry, (a) a step of removing pyrite from pyrite-containing slurry to form an inert flow and pyrite-containing material as described herein, wherein the pyrite-containing slurry includes tailings from a tailings dam or ore processing plant, (b) A method is provided comprising the steps of (b) leaching a metal sulfide-containing material and a pyrite-containing material with a leachate and microorganisms to remove metal from the metal sulfide-containing material and form a metal-containing leachate, wherein the pyrite in the pyrite-containing material generates acid and heat that promotes the leaching of metal from the metal sulfide-containing material, and microorganisms oxidize ferrous to ferric.

[0037] As used herein with respect to inert flows, the term “inert” should be understood to mean that the flow is less reactive than the slurry introduced into the method, with respect to the amount of pyrite in the flow.

[0038] As used herein, the term “pyrite-containing slurry” should be understood to mean any slurry containing amounts of pyrite that, if untreated / uncontrolled, would pose an environmental hazard.

[0039] The term "ore processing plant" should be understood herein to mean any suitable plant for recovering metals from ore.

[0040] The term “ore” should be understood herein to mean natural rock or precipitate containing one or more valuable minerals, typically containing valuable metals, that can be mined, processed, and sold for profit.

[0041] Metal sulfide-containing materials can originate from any suitable mined material.

[0042] The method described above has the following advantages: This method allows for the processing of pyrite-containing tailings, thereby reducing the volume of existing tailings dams. This is a significant environmental outcome, typically involving minimal use of resources. The removal of pyrite from pyrite-containing slurry from a tailings dam or ore processing plant according to the present invention produces two useful "products" as a result of the present invention. • One product is an inert flow. As defined above, "inert" means that the flow is less reactive than the input slurry to the method with respect to the amount of pyrite in the inert flow. This is beneficial because pyrite "acidifies" the tailings, and since this is a problem of tailings disposal, pyrite in tailings is an environmental problem. This method offers the opportunity to produce an environmentally safe output for use in downstream applications such as copper or nickel or zinc or cobalt ore processing plants (in the case of the aqueous portion of the inert flow) and land cover / filling materials (in the case of the solid portion of the inert flow). With respect to the land cover / filling material opportunity, this is possible by considering the reduction or substantial elimination of the ability of the solid portion to produce acidic wastewater. The second product is a pyrite-containing material that is usefully used as a pyrite source in the downstream method steps of the present invention, thereby minimizing the harmful environmental impact of pyrite. For example, the pyrite-containing material of the second product can be usefully used in method steps for recovering metal sulfide-containing materials such as copper, nickel, zinc, or cobalt from metal sulfide-containing materials, such as low-grade copper sulfide-containing materials, such as waste rock, through depositional leaching of metal sulfide-containing materials. In this regard, the acidic and exothermic capacity of pyrite is an advantage in depositional leaching. For example, pyrite can reduce the amount of acid added to the leaching solution. In addition, the oxidation of pyrite is a very exothermic reaction, and the heat generated allows for high-temperature leaching, resulting in a faster and more complete extraction of metals during depositional leaching. It should be noted that any metal such as copper, nickel, zinc, or cobalt in the pyrite-containing material is an additional benefit, as it is incorporated into the deposition along with the pyrite and can be recovered in the depositional leaching step. This method is readily available and can be operated using tested and verified equipment. This method allows for the processing of materials previously classified as metal sulfide-containing waste, such as tailings and waste rock, reducing the environmental impact of these materials while optimizing the recovery of value from the originally mined materials.

[0043] The term "low-grade" as used in the phrase "low-grade copper sulfide-containing materials" above is understood in this specification to be a term dependent on currently available technology and the current price of copper. It should be noted that materials currently considered "low-grade" may be considered valuable materials in the future, depending on technological developments and the future price of copper.

[0044] The pyrite removal step (a) may include treating the pyrite-containing slurry by any method for recovering pyrite from the slurry.

[0045] The pyrite removal step (a) may include treating the pyrite-containing slurry by any method of recovering and concentrating pyrite from the slurry.

[0046] The pyrite removal step (a) may include the steps of (i) suspending the pyrite-containing material in the pyrite-containing slurry, and (ii) generating an inert flow as one flotation product, and (ii) generating the pyrite-containing material, such as a pyrite-containing concentrate flow, as another flotation product.

[0047] The pyrite removal step (a) may include a size separation step in the pyrite-containing slurry, prior to the flotation step described above, in which larger particles in the pyrite-containing material are separated from the pyrite-containing slurry via a cyclone or other suitable sorting device, for example, and the remaining pyrite-containing slurry is transferred to the flotation step.

[0048] The term "cyclone" as used herein should be understood to describe a device capable of classifying, separating, or sorting particles in a liquid suspension based on the ratio of their centripetal force to fluid resistance. This ratio is high for dense (where separation by density is required) and coarse (where separation by size is required) particles, and low for light and fine particles.

[0049] The pyrite removal step (a) may include reducing the size of larger particles in the pyrite-containing material within a size reduction circuit, and returning the reduced-size particles to the size separation step.

[0050] The pyrite removal step (a) may include selecting operating conditions for a size separation step such that the pyrite particles in the pyrite-containing material in the remaining pyrite-containing slurry have a particle size distribution necessary for, for example, downstream treatment of tailings in a sedimentation leaching operation.

[0051] The pyrite removal step (a) may include a step of thickening and / or filtering the pyrite-containing material flow, and a step of dewatering the flow to form a pyrite-containing concentrate.

[0052] This method may include any suitable downstream processing steps for the inert flow generated in the pyrite removal step (a).

[0053] The processing step may include using an aqueous portion of an inert flow as a water source in a processing plant for recovering copper, nickel, zinc, or cobalt from ore containing at least one of these metals.

[0054] The solid portion of the inert flow can be used as a cover / filling material to seal tailings dams and generally fill voids within waste rock dams, for example, by mixing tailings with waste rock before disposal.

[0055] The solid portion can also be used as a building material, such as in the manufacture of concrete or brick.

[0056] Furthermore, the solid portion can also be used as a carbonate mineral to sequester CO2 from the atmosphere.

[0057] The leaching step (b) may include any suitable leaching step for leaching a metal such as copper, nickel, zinc, or cobalt from the metal sulfide-containing material.

[0058] Typically, pyrite is present in a concentration of 1–10% by weight of the total mass of the copper sulfide-containing material and the pyrite-containing material.

[0059] This method may include a step of mixing the metal sulfide-containing material and the pyrite-containing material together before the leaching step (b).

[0060] This method may include a step prior to the leaching step (b) in which the metal sulfide-containing material and the pyrite-containing material are mixed together to form aggregates of these materials.

[0061] As an example, step (b) is: i. A step of mixing metal sulfide-containing materials such as pyrite-containing material and copper sulfide-containing material to form aggregates, ii. A step of depositing and leaching metals such as copper from the aggregate to produce a noble liquid leachate containing metals such as copper in a solution, iii. A step of recovering metals such as copper from the leached noble liquid, It can include...

[0062] Pyrite particles in pyrite-containing materials have a P value of 1 mm or less than 1 mm. 80 It may have a particle size of [specify particle size].

[0063] The pyrite particles in the pyrite-containing material are 250 μm P 80 It may have a particle size of or less than 250 μm.

[0064] The agglomeration step (i) can be any suitable step for agglomerating the pyrite-containing material and the copper sulfide-containing material.

[0065] The agglomeration step (i) may include mixing the pyrite-containing material with a metal sulfide-containing material, such as a copper sulfide-containing material, and agglomerating them.

[0066] The mixing step may be performed before the aggregation step.

[0067] The mixing step and the agglomeration step can be performed simultaneously.

[0068] Metal sulfide-containing materials can originate from any suitable mined material.

[0069] The metal can be copper.

[0070] In that case, for example, the metal sulfide-containing material could be a copper sulfide-containing material.

[0071] The copper sulfide-containing material can be any suitable copper sulfide-containing material, such as copper sulfide minerals.

[0072] An example of a copper sulfide-containing material is rock containing low concentrations of copper, which can be considered, for example, waste rock.

[0073] Copper sulfide-containing materials may be mined materials or waste stockpiles containing copper sulfide, with regard to the above explanation of the term "low grade" as used in the phrase "low grade copper sulfide-containing materials," i.e., low concentrations of copper in the material.

[0074] In other words, copper sulfide-containing materials may be mined materials, or stockpiled materials, that are considered too low-grade to be economically processed using flotation and other wet treatment systems for recovering copper from copper-containing ore and concentrate.

[0075] More specifically, the copper sulfide-containing material may be the same as the mined material, or it may be from stockpiles that are too low in grade to be economically treated by any other treatment method, including sedimentation leaching.

[0076] In the context of the previous three paragraphs, the term “low copper concentration” should be understood to mean an average copper concentration of 1.5% or less by weight, typically 1.2% or less by weight, more typically 1.0% or less by weight, even more typically 0.7% or less by weight, even more typically 0.5% or less by weight, even more typically 0.3% or less by weight, and even more typically 0.1% or less by weight.

[0077] The present invention also relates to a deposition leaching method for mined materials containing metals such as copper, nickel, zinc, or cobalt in a metal sulfide-containing material, (a)(i) a pyrite-containing material produced from pyrite-containing slurry such as pyrite-containing tailings from a tailings dam or ore processing plant, and (ii) a mined material containing metals such as copper, nickel, zinc, or cobalt in a metal sulfide-containing material, the step of leaching the aggregates produced from the material using a leachate and microorganisms, wherein the pyrite in the pyrite-containing material generates acid and heat that facilitates the leaching of metals from the mined material, and the microorganisms oxidize ferrous to ferric, (b) A method is provided which is characterized by the step of collecting a noble liquid leachate containing metal in solution from the deposit.

[0078] The deposition leaching method also includes recovering metals from the leached noble liquid.

[0079] The present invention also relates to a deposition method for leaching metals such as copper, nickel, zinc, or cobalt from metal sulfide-containing materials in mined materials, (a)(i) Pyrite-containing material produced from pyrite-containing slurry such as pyrite-containing tailings from tailing dams or ore processing plants, and (ii) Deposit of aggregates produced from mined material containing metals such as copper, nickel, zinc, or cobalt in metal sulfide-containing material, (b)(i) supplying leachate and microorganisms to the deposit so that the leachate flows downward through the deposit and leaches metal from the mined material, and (ii) collecting the metal-containing leachate from the deposit, a system in which pyrite generates acid and heat to facilitate the leaching of metal from the mined material in the deposit, and microorganisms oxidize ferrous to ferric, It provides a deposit that includes [this].

[0080] Pyrite may make up 1 to 10% by weight of the total mass of the aggregate.

[0081] In a broader sense, the present invention also relates to a method of mining. (a) A step of mining metal sulfide-containing ore such as copper sulfide-containing ore, (b) A step of processing metal sulfide-containing ore in an ore processing plant to produce pyrite-containing slurry, (c) Method for processing the pyrite-containing slurry described above, This provides a method that includes this.

[0082] The present invention also relates to a flotation circuit for an ore processing plant for metal sulfide-containing materials, (a) A pulverizer feed flotation circuit for generating tailings and concentrate from a pulverizer feed, wherein the tailings include a metal sulfide-containing material, and the pulverizer feed flotation circuit (b) A pyrite flotation circuit and tailings flow for generating a pyrite concentrate flow, i.e., a pyrite-containing slurry, A flotation circuit is provided that includes this.

[0083] The pyrite flotation circuit may be configured to process a pyrite concentrate stream, i.e., a pyrite-containing slurry, in accordance with the method for processing the pyrite-containing slurry described above.

[0084] The crusher feed flotation circuit may be any suitable circuit.

[0085] The crusher feed flotation circuit can include coarse sorter / capture cells and bulk cleaner cells. These can be standard coarse sorter / capture cells and bulk cleaner cells. They can be existing cells in an ore processing plant. They can be cells in a greenfield plant.

[0086] The coarse sorter / capture cell and bulk cleaner cell may be configured such that (i) the coarse sorter / capture cell processes the crusher feed and generates a first tailings stream and a concentrate stream, and (ii) the bulk cleaner cell processes the concentrate stream and generates a second tailings stream and another concentrate stream, and transfers the other concentrate stream and the second tailings stream to the pyrite flotation circuit for further processing such as metal recovery and processing in its circuit.

[0087] Metal sulfide-containing materials can be copper sulfide-containing materials such as copper sulfide-containing minerals.

[0088] The pulverizer feed can be any appropriate particle size distribution of the metal sulfide-containing material.

[0089] The ore processing plant may include any suitable upstream grinding circuit for generating grinder feed, as well as downstream recovery and tailings storage or other options.

[0090] The present invention also provides an ore processing plant for metal sulfide-containing materials, including the flotation circuit described above.

[0091] The ore processing plant may also include any suitable upstream grinding circuitry as well as downstream recovery and tailings storage and / or processing options.

[0092] Metal sulfide-containing materials can be copper sulfide-containing materials such as copper sulfide-containing minerals.

[0093] The present invention also relates to a deposition leaching operation for leaching metals such as copper, nickel, zinc, or cobalt from metal sulfide-containing material in mined material, (a) Deposition of aggregates of pyrite and other metal sulfide-containing materials, such as pyrite, resulting from the above-mentioned treatment method for pyrite-containing slurry, (b) (i) supplying leachate and microorganisms to the deposit so that the leachate flows downward through the deposit and leaches metal from the metal sulfide-containing material, (ii) collecting the metal-containing leachate from the deposit, generating acid and heat in the deposit to facilitate the pyrite leaching metal from the metal sulfide-containing material, the pyrite being in or originating from a pyrite-containing slurry such as tailings, and a system in which microorganisms oxidize ferrous to ferric, The system provides a deposition and leaching operation that includes this process.

[0094] Metal sulfide-containing materials can originate from any suitable mined material.

[0095] As stated above, the term “mined material” should be understood herein to include material that has been mined and transported from the mine to (a) downstream processing operations for the direct recovery of metals from the material, or (b) to a stockpile for subsequent processing.

[0096] The present invention is further described below as merely an example with reference to the following drawings. [Brief explanation of the drawing]

[0097] [Figure 1] For example, this is a flowchart illustrating one embodiment of a method for processing by beneficiating pyrite-containing tailings, i.e., pyrite-containing slurry, and then beneficiating the pyrite removed from the tailings in the downstream sedimentation and leaching of copper sulfide-containing material. [Figure 2] Graphs of copper extraction time versus leaching time for a series of column bioleaching tests performed on (i) ore samples from a copper mine, (ii) copper ore enhanced with pulverized museum-grade pyrite, and (iii) copper ore enhanced with pyrite concentrate produced by flotation of tailings generated in a copper mine. [Figure 3] This is a flowchart of one embodiment of a flotation circuit for an ore processing plant according to the present invention. [Modes for carrying out the invention]

[0098] For example, one embodiment of the ore-dressing method involves ore-dressing a pyrite-containing slurry in the form of tailings from a mine tailings dam or ore processing plant according to the present invention, as shown in Figure 1, thereby removing pyrite from the tailings, generating an inert flow suitable for use in downstream applications, and producing pyrite-containing material that can be used beneficially in the downstream deposition and leaching of copper sulfide-containing materials, as described below, thereby minimizing the harmful environmental impact of pyrite.

[0099] In other words, this embodiment produces two "products" from a pyrite-containing slurry.

[0100] The present invention is not limited to these embodiments and should be understood to generally extend to methods for processing pyrite-containing slurries, such as pyrite-containing tailings produced in mines, comprising the steps of removing pyrite from the slurry, for example by beneficiation, and forming two “products” in the form of a solid material, such as a solid concentrate, which can be used for purposes other than the deposition and leaching of downstream copper sulfide-containing materials.

[0101] It should be noted that the pyrite-containing slurry may be any suitable pyrite-containing slurry, such as tailings from an ore processing plant. Example 2 and Figure 3 illustrate an embodiment of the flotation circuit according to the present invention for producing a suitable pyrite-containing slurry.

[0102] Generally speaking, the embodiment shown in Figure 1 includes a method for removing copper from a low-grade copper-containing material having copper sulfide minerals, the method comprising the steps of leaching the low-grade copper-containing material and pyrite, generating a leached liquid, and recovering copper from the leached liquid, the pyrite being generated from a pyrite-containing slurry.

[0103] Generally speaking, the embodiment shown in Figure 1 is a method of mining, (a) The step of mining copper sulfide-containing materials such as copper sulfide-containing minerals and stockpiling them at the discretion of the owner, (b) The steps of (i) processing the copper sulfide-containing ore described herein in a copper sulfide-containing material at an ore processing plant, and (ii) recovering copper, and (ii) producing a pyrite-containing slurry. (c) A step of processing a pyrite-containing slurry, and a step of producing pyrite, (d) The step of treating the “uneconomical” low-grade copper sulfide-containing material described herein with pyrite by a deposition and leaching operation, This method includes [something].

[0104] Referring to Figure 1, the method for processing pyrite-containing slurry and generating pyrite, as well as for the downstream use of pyrite, is more specifically as follows: (a) Separation steps 15, 16, 17, 18, 19, 20 which process pyrite-containing tailings from a mine tailings dam or ore processing plant (not shown in Figure 1, but partially shown as an example in Figure 3) to produce two “products” in the form of (i) a solid pyrite-containing concentrate flow 20 and (ii) an inert flow from the tailings, (b) an aggregation step 4 in which the pyrite-containing concentrate flow 20 from the separation step and (ii) at least one copper sulfide-containing solid material treated in steps 1, 2, and 3 are mixed and aggregated, (c) Deposition and leaching step 6 involves leaching copper from the copper sulfide-containing material in the aggregates generated in step 4 to produce a leached noble liquid, (d) Copper recovery steps 9 and 10, in which copper is recovered from the leachate extracted from the sediment, Includes.

[0105] Separation steps 15, 16, 17, 18, 19, 20 of pyrite-containing tailings Typically, tailings are the output of an ore processing plant used to recover copper from copper sulfide-containing ores that contain copper sulfide-containing materials such as copper sulfide minerals.

[0106] The ore processing plant may be any suitable plant.

[0107] An example of an ore processing plant includes the crushing of mined ore, which comprises a series of crushing and grinding steps, and one or more flotation circuits (described above and in Example 2 as “Crusher Supply”) for flotating copper sulfide minerals from the crushed ore, and the production of valuable concentrate and tailings (pyrite-containing slurry).

[0108] Typically, the solids in tailings are in the form of (a) a fine slurry containing low concentrations of copper, typically less than 0.4 wt%, and more typically less than 0.3 wt%, and (b) pyrite-containing particles suspended in water. Typically, these fine particles and pyrite-containing particles precipitate slowly. The pyrite-containing particles may also contain some copper.

[0109] The tailings are transported, for example, directly from an ore processing plant, from a tailings dam or other suitable tailings source 15 by being pumped into a series of cyclones 16, or into any other suitable size separation option that separates larger solids from the remaining fine-grained tailings and forms two separate flows.

[0110] Cyclone 16 may be any suitable cyclone.

[0111] Larger solids from cyclone 16 are processed in size reduction circuits such as milling / grinding / polishing circuit 17, which reduces the particle size of the larger solids.

[0112] The output of this circuit is returned to cyclone 16 for further processing within the cyclone.

[0113] The operating conditions for Cyclone 16 are selected such that the pyrite-containing particles in the remaining tailings have the particle size distribution required for the deposition and leaching step 5. In this regard, typically, the pyrite-containing particles in the remaining tailings have a particle size of 1 mm or less than 1 P 80 It has a particle size of 250 μm or less than 250 μm. More typically, pyrite particles in the remaining tailings are P 80 It has a particle size value.

[0114] The remaining tailings from cyclone 16 are transferred to a first flotation circuit 18 (described in Example 2 in relation to Figure 3 as the "pyrite flotation cell") and processed within the circuit. Appropriate flotation agents are added to the circuit as needed. Operating conditions, including the reagents, are selected to suspend pyrite-containing particles. Typically, these operating conditions also suspend copper particles.

[0115] The underflow from the first flotation circuit forms the inert flow described above. As stated above, the term “inert” means that the flow is less reactive than the input slurry to the method with respect to the amount of pyrite in the flow. In the context of Figure 1, this means that the underflow flow is less reactive than the pyrite-containing tailings supplied to the method with respect to the amount of pyrite in the flow. As stated above, pyrite makes the tailings “acidifying tailings,” which is beneficial because pyrite in tailings is an environmental problem, and this is a problem of tailings disposal. This method offers the opportunity to produce an environmentally safe product for use in downstream applications such as copper ore processing plants and can reduce the requirement for an oxidizer (ferric). Ferric (produced by microbial oxidation of ferrous dissolution from iron-containing minerals in pyrite concentrate and waste rock) oxidizes pyrite and copper sulfide minerals. In the embodiment of Figure 1, the underflow flow for the first flotation circuit is transferred to the downstream neutralization step 11 described later.

[0116] The overflow, or flotation flow, from the first flotation circuit is transferred to and processed in the second flotation circuit 19 (described in Example 2 in relation to Figure 3 as the "pyrite flotation cell").

[0117] A suitable flotation agent is added to the second flotation circuit 19 as needed. The operating conditions, including the reagent, are selected to suspend the pyrite-containing particles.

[0118] The underflow from the second flotation circuit is returned to the first flotation circuit.

[0119] The pyrite-containing overflow from the second flotation circuit is transferred to the thickener 20, where it is dehydrated to form a pyrite-containing concentrate.

[0120] The pyrite-containing concentrate is transferred from the thickener 20 to the aggregation step 4 described later.

[0121] The embodiments described have two flotation circuits 18 and 19, but it should be noted that the present invention is not limited to this number of circuits.

[0122] The embodiments described include a cyclone 16 and a milling / grinding / polishing circuit 17 that returns the material to the cyclone 16, but it should be noted that the present invention is not limited to this configuration.

[0123] For example, the combination of the cyclone 16 and the milling / grinding / polishing circuit 17 is not necessary if the particle size distribution in the tailings supplied from the tailings dam or other suitable tailings source 15 is suitable for downstream processing after the separation step.

[0124] As a further example, if there is a downstream step to optimize the particle size distribution of pyrite particles in pyrite-containing concentrate, the combination of cyclone 16 and milling / grinding / polishing circuit 17 is not necessary.

[0125] Aggregation step 4 Aggregation step 4 is, (a) The pyrite-containing concentrate derived from the tailings described above, (b) The copper sulfide-containing material produced in steps 2 and 3, To aggregate.

[0126] The copper sulfide-containing material in this embodiment of the method of the present invention includes copper sulfide-containing waste rock, which is discussed in the following sections.

[0127] It should be noted that copper sulfide-containing materials can be any suitable copper sulfide-containing material, taking into account characteristics such as the particle size distribution of tailings concentrate and the requirements for downstream processing of aggregates.

[0128] Step 4 can be any suitable agglomeration step using any suitable equipment such as an agglomeration drum.

[0129] For example, the required proportions of pyrite concentrate and copper sulfide-containing material are added to a mixing apparatus and mixed together, with or without binders, with or without acid, with or without water, and with or without reused leaching solution.

[0130] The required ratio depends on factors such as the amount of pyrite in the rock. Typically, the broad pyrite concentration range of the mixed product is 1–10% by weight of pyrite.

[0131] The selection of binders and acids, as well as the addition of water and / or recycled leaching solutions, are functions of several factors, including the properties of pyrite-containing concentrates and copper sulfide-containing feedstocks, and the required mechanical properties of the aggregates.

[0132] Agglomeration step 4 may include, if necessary, any suitable protocol for adding and mixing pyrite-containing concentrate, copper sulfide-containing solid feed material, and binders and water.

[0133] The aggregates are stored in stack 5 and then transferred to the deposition and leaching step described later.

[0134] Copper-containing material processing steps 1, 2, and 3 In the flowchart shown in Figure 1, the copper sulfide-containing material is in the form of waste rock containing low-grade copper, re-mined from stockpile 1.

[0135] As described above, these stockpiles are currently considered to be of too low grade to be economically processed using flotation and other ore processing systems for recovering copper from copper sulfide-containing ore and concentrate.

[0136] As described above, the present invention is not limited to the source of this copper sulfide-containing material.

[0137] For example, copper sulfide-containing materials may be materials that are considered too low-grade to be economically processed for copper recovery by known conventional methods in a test operation carried out in the mining area before mining (e.g., by drilling and blasting) and then transported directly from the mine (without being stockpiled) for processing in steps 2 and 3 after mining.

[0138] The stored waste rock 1 is transported to a crushing circuit in a suitable vehicle such as a transport truck or front-end loader, or on a conveyor belt, and is crushed and milled in primary, secondary, and tertiary crushing circuits 2 and 3 to the extent necessary to produce a particle size distribution suitable for the agglomeration step 4.

[0139] The grinding circuits 2 and 3 include one or more grinding steps that deliver the ground copper-containing material to one or more milling and size sorting steps, and can generate a grinding product stream having a desired particle size distribution for the agglomeration step 4.

[0140] The grinding steps 2 and 3 can be performed using a combination of a swivel grinder, a cone grinder, and a high-pressure grinding roll (HPGR) grinder (not shown).

[0141] The resulting pulverized copper sulfide-containing material is transferred to the agglomeration step 4.

[0142] Sedimentation leaching, downstream solvent extraction, and electrolysis steps 5, 6, 9, 10, 11, 12 Aggregates from stack 5, forming a deposit 6 of aggregates on the leachate pad.

[0143] Sediment 6 may be any suitable sedimentary structure. (a) A leachate storage and delivery system that supplies leachate to the upper surface of the deposit, (b) A leachate collection system for collecting copper-containing leachate in a solution extracted from copper sulfide-containing material in a sediment aggregate, (c) Microorganisms (such as bacteria or archaea) or other suitable oxidizing agents for oxidizing ferrous to ferric, wherein ferric is an oxidizing agent in the leaching process, To equip with.

[0144] The leached noble liquid is processed in a solvent extraction system 9, which extracts copper from the solution in an organic medium, then removes the copper from the organic medium, and produces a copper-containing solution.

[0145] The copper-containing solution is transferred to the electrolytic extraction plant 10, where copper is recovered from the solution.

[0146] The extractant residue from the solvent extraction system 9 is regenerated and returned to the deposit as leachate. The leachate regeneration system includes an extractant residue drain limestone / lime neutralization step 11 to control the accumulation of impurities and to produce neutralized solids for separate storage in a neutralization residue storage facility 12, or possibly for co-storage with tailings.

[0147] Pyrite concentrates within aggregates provide a valuable source of acid and heat via pyrite.

[0148] The acid-generating properties of pyrite mean that the amount of acid that must be added to the leachate to maintain a given leaching acid requirement can be reduced.

[0149] In addition, microbial oxidation of pyrite generates acid and heat, all of which are beneficial for depositing and leaching copper sulfide-containing materials.

[0150] Advantages of the embodiment shown in Figure 1 The embodiments shown in Figure 1 and the advantages of the present invention generally include the following advantages. The embodiment makes it possible to produce two output "products" from pyrite-containing tailings. • One of the products is an inert flow. The second product is pyrite concentrate, which can be usefully used in downstream depositional leaching methods for copper-containing materials. The main focus of this application is the useful use of pyrite to generate acid and heat in deposition to generate high temperatures that reduce the additional acid requirements for depositional leaching and increase the rate and degree of copper extraction from copper-containing materials. The embodiment reduces the environmental impact of pyrite-containing tailings and enables the beneficial use of at least the extracted pyrite. The embodiment enables low-cost optimization of copper recovery from mined materials while minimizing environmental impact and resource use. The embodiments utilize readily available, tested, and verified equipment.

[0151] Example 1 The applicant conducted a column bioleaching test to investigate the effect of pyrite enhancement on the bioleaching of copper ore.

[0152] Columnar bioleaching tests evaluated copper extraction time versus leaching time for (i) ore samples from copper mines, (ii) copper ore enhanced with pulverized museum-grade pyrite, and (iii) copper ore enhanced with pyrite concentrate produced by flotation of tailings generated in copper mines.

[0153] A sample of ore from a copper mine, 9mm P 80 The material was then crushed to less than 12 mm and approximately 10 kg of this material was added to a flocculation drum using water and concentrated sulfuric acid.

[0154] In the pyrite-added tests, either nearly pure museum-grade pyrite or fine pyrite concentrate produced by flotation of tailings generated in copper mines was mixed with the ore in the agglomeration drum to increase or enhance the pyrite content of the aggregate material from the naturally occurring 0.86 wt% pyrite in the ore to 4.0% pyrite. Both pyrite samples used were very fine, with particles of 150 μm. 100 The sample was subjected to elemental and mineral analysis.

[0155] The term "museum-grade pyrite" is to be noted as being understood in this specification to mean a pyrite content of greater than 90 wt%, typically greater than 95 wt%, typically greater than 97 wt%, or more typically greater than 99 wt%. Museum-grade pyrite may have a silver content of less than 1 mg / kg, typically less than 0.5 mg / kg, typically less than 0.2 mg / kg, or more typically less than 0.1 mg / kg.

[0156] Table 1 summarizes the elemental and mineral compositions of the ores, museum-grade pyrite, and pyrite concentrate used in the tests.

[0157]

Table 1

[0158] Once mixed, the aggregate material was filled into columns 1 m in height and 0.1 m in diameter and cured at room temperature for 2 - 5 days before leaching was initiated. During leaching, the temperature of the columns was controlled at 50 °C using a heating jacket, and the columns were aerated at 0.102 Nm 3 / h / ton ore. The columns were inoculated with ferrous iron-oxidizing and sulfur-oxidizing microorganisms, and a wash solution initially containing 5 g / L of ferrous iron as ferrous sulfate was pumped into the top of the columns at 10 L / h / m 2 through a dripper and collected at the bottom of the columns.

[0159] The pH of the recovered leach solution was adjusted to a target pH of 1.2 using sulfuric acid as necessary and then returned to the top of the columns for reuse. Solution samples were taken periodically for analysis of their metal and sulfate concentrations.

[0160] The wash solution had a sulfate concentration of approximately 20 g / L at the start of leaching. When the sulfate concentration in the solution exceeded 120 g / L, the solution was diluted to maintain a maximum of 120 g / L of sulfate for the addition of sulfuric acid and the oxidation of sulfide minerals.

[0161] If the copper concentration in the solution exceeded 8 g / L, the solution was subjected to ion exchange to remove copper and reduce the copper concentration to below 8 g / L in order to leach it out.

[0162] Column analysis was performed under leaching for 350 days. Upon completion of leaching, the column was rinsed first with dilute sulfuric acid and then with water to remove dissolved metals and sulfates from the entrained leaching solution. The column was then emptied, the solids were dried, and analyzed together with the final leaching solution. A mass balance was performed, and copper extraction was reported based on the calculated copper head analysis.

[0163] Figure 2 is a graph showing copper extraction versus leaching time for three column tests, and Table 2 summarizes the copper and sulfide mineral extractions achieved.

[0164] [Table 2]

[0165] The beneficial effect of enhancing ore with pyrite on copper extraction is evident from Figure 2 and Table 2.

[0166] Copper extraction was increased by 11.5% and 14.4% respectively by adding museum-grade pyrite and pyrite concentrate. The improvement in copper extraction is thought to be due to the increased availability of ferric pyrite resulting from the oxidation and leaching of the added pyrite, which has a fine particle size (150 μm). 100 It responded quickly for this reason. This is evident from the pyrite extraction results shown in Table 2. Pyrite extraction from the ore was only 50.0%, but pyrite extraction from ore enhanced with museum-grade pyrite and pyrite concentrate was much higher, reaching 90.2% and 89.4%, respectively.

[0167] Notably, copper extraction was very high in all three tests, with a fine particle fraction of -150 μm: 87.1% in the test on ore, 90.2% in the test on ore enhanced with museum-grade pyrite, and 92.0% in the test on ore enhanced with pyrite concentrate. The results indicate that copper minerals contained in the ore fine particles, as well as P in both cases, were -150 μm. 100 This demonstrates that very high copper extraction was achieved from copper minerals in two pyrite-enhanced materials with particle size. The natural silver content of the column feed sample, expressed as g Ag / kg CuFeS2 in Table 2, is thought to have had a beneficial catalytic effect, improving the recovery of copper from chalcopyrite (as taught in the present applicant's international application PCT / AU2018 / 050316 (International Publication No. 2018 / 184071)), particularly from chalcopyrite in fine fragments.

[0168] Therefore, the present invention provides a means for achieving very high copper extraction from copper minerals contained in pyrite enhancers, and also provides high copper extraction from copper minerals contained in ore.

[0169] Example 2 The objective of Example 2 was to demonstrate the effectiveness of removing pyrite from pyrite-containing slurry generated in the flotation circuit of an ore processing plant.

[0170] Figure 3 is a flowchart of one embodiment of the flotation circuit 23 for an ore processing plant according to the present invention.

[0171] The ore processing plant may include any suitable upstream grinding circuitry as well as downstream recovery and tailings storage or other options (not shown).

[0172] The flotation circuit 22 shown in Figure 3 includes a coarse sorter / capturer cell 25 and a bulk cleaner cell 27. These can be standard coarse sorter / capturer cells and bulk cleaner cells. They can be existing cells in an ore processing plant. They can be cells in a greenfield plant.

[0173] The flotation circuit 22 shown in Figure 3 also includes a pyrite flotation cell 29 of the type described above in relation to Figure 1, it should be noted that Figure 1 includes two cells 18, 19, and Figure 2 shows a single cell 29. It should be noted that the present invention extends to any suitable number of pyrite flotation cells having, if necessary, size separation and regrinding options 16, 17 as shown in Figure 1, for example, as well as other options for processing the feed material to the cells.

[0174] During use, the crusher feed 31 is transferred to the coarse sorter / capturer cell 25, which generates a concentrate flow 33 and a first tailings flow 35. The crusher feed 31 may be any suitable crusher feed produced by a combination of crushing, grinding, and size separation steps, which may be, for example, an existing crushing circuit in an ore processing plant or a circuit designed to suit the purpose of a greenfield plant.

[0175] The first tailings stream 35 is transferred to a storage area 37. This may be a tailings dam or other tailings processing option.

[0176] The concentrate stream 33 from the coarse sorter / capturer cell 25 is transferred to the bulk cleaner cell 27, which generates a plant concentrate stream 39 and a second tailings stream 41.

[0177] The plant concentrate flow 39 from the bulk cleaner cell 27 is transferred for the recovery of copper and other metals such as molybdenum. The recovery option may be any suitable option.

[0178] The second tailings stream 41 from the bulk cleaner cell 27 is transferred to the pyrite flotation cell 29, which generates a pyrite-containing concentrate stream 43 and a third tailings stream 45.

[0179] The first and third tailing streams 35, 45, and optionally a portion of the second tailing stream 41, are transferred to a storage location such as a tailing storage facility or other tailing processing options.

[0180] The pyrite-containing concentrate stream 43 is transported for further processing, such as aggregation, and for use in the aforementioned deposition and leaching circuit as shown in Figure 1.

[0181] The applicant conducted a large-scale flotation test on the scavenger / cleaner tailings in the pyrite flotation cell shown in Figure 3, i.e., the sample of the second tailings stream. The results are shown below.

[0182] Table 3 summarizes the composition of the pyrite concentrate obtained from the trapping / cleaner tailings feed in the pyrite flotation cell, i.e., from the second tailings stream.

[0183] The table shows the effectiveness of using flotation to recover pyrite (and copper minerals, which is a significant advantage) from pyrite concentrate flows from tailings (see rows 1-10).

[0184] This process produced pyrite concentrate in a grade of 83% pyrite and 2.2% copper, and coarse / captured tailings in a pyrite grade of less than 0.8% pyrite.

[0185] [Table 3]

[0186] Table 4 provides a summary of key results from large-scale pyrite flotation experiments, showing that 78% by weight of the pyrite initially contained in tailings samples was recovered into pyrite concentrate.

[0187] [Table 4]

[0188] Grab samples from the pyrite flotation feed, i.e., the second tailings stream 41, and the pyrite flotation cell tailings, i.e., the third tailings stream 45, were subjected to acid / base accounting (ABA) testing. A summary of the results is shown in Table 5.

[0189] [Table 5]

[0190] The ABA results show a decrease in the reported pyrite (lower AP) relative to tailings, i.e., second and third tailing flows 41, 45. The negative NNP (net neutralization potential) indicates that the pyrite flotation cell feed, i.e., second tailing flow 41, is the net acid generator, and the ratio of pyrite flotation cell tailings, i.e., third tailing flow 45, to over 1 (6.42) indicates that the inert flow (i.e., flotation tailings) can be used as a land cover / filling material.

[0191] As is clear from the above, the flotation circuit shown in Figure 3 is an effective circuit for generating pyrite concentrate flow, i.e., pyrite-containing slurry that can be used, for example, in the deposition leaching operation described above in relation to Figure 1.

[0192] Many modifications can be made to the flowchart in Figure 1 without departing from the spirit and scope of the present invention.

[0193] For example, the embodiment includes a "cyclone" step 16, but the present invention extends to the use of any suitable size separation step.

[0194] In addition, while the embodiments include steps 1-3 of processing waste rock to form a copper sulfide-containing material which is one feed for agglomeration step 4, the present invention is not limited to this combination of steps, and the waste rock can be processed in any suitable step to produce a suitable feed material for agglomeration step 4.

[0195] In addition, although the embodiments are described in the context of recovering copper, it should be noted that the present invention is not limited to copper and extends to recovering metals such as nickel, zinc, or cobalt from waste rock containing at least one of these metals in a metal sulfide-containing material.

[0196] In addition, while the embodiments focus on tailings from wet processing plants for copper sulfide-containing ores, the present invention also extends to tailings derived from the processing of ores containing other metals such as cobalt, nickel, and zinc.

Claims

1. A method for processing pyrite-containing slurry, Pyrite removal step (a): A step of removing pyrite from the pyrite-containing slurry to form (i) an inert flow and (ii) a pyrite-containing material, wherein the pyrite-containing slurry includes tailings from a tailings dam or ore processing plant, Leaching step (b): A step of leaching the metal sulfide-containing material and the pyrite-containing material with an acidic leachate and microorganisms to remove the metal from the metal sulfide-containing material and form a metal-containing leachate, wherein the pyrite in the pyrite-containing material generates acid and heat that promotes the leaching of the metal from the metal sulfide-containing material, and the microorganisms oxidize ferrous to ferric, Includes, A method wherein the metal is copper, nickel, zinc, or cobalt.

2. The method according to claim 1, wherein the pyrite removal step (a) includes a flotation step of suspending the pyrite-containing material in the pyrite-containing slurry, and a generation step of (i) generating the inert flow as one flotation product, and (ii) generating the pyrite-containing material as another flotation product.

3. The method according to claim 2, wherein, prior to the flotation step, the pyrite removal step (a) includes a size separation step, the size separation step separating larger particles in the pyrite-containing material from the pyrite-containing slurry, and the remaining pyrite-containing slurry after the size separation step is transferred to the flotation step.

4. The method according to claim 3, wherein the pyrite removal step (a) includes the steps of reducing the size of the larger particles in the pyrite-containing material within a size reduction circuit, and returning the reduced-size particles to the size separation step.

5. The method according to claim 3, wherein the pyrite removal step (a) includes the step of selecting operating conditions such that the pyrite particles in the pyrite-containing material in the remaining pyrite-containing slurry have the particle size distribution required for the leaching step (b) provided downstream of the pyrite removal step.

6. The pyrite particles in the pyrite-containing material have a P value of 1 mm or less than 1 mm. ８０ The method according to claim 1, having a particle size of the specified value.

7. The pyrite particles in the pyrite-containing material have a P value of 250 μm or less than 250 μm. ８０ The method according to claim 5, having a particle size value of

8. The method according to claim 1, wherein the pyrite removal step (a) includes the steps of thickening and / or filtering the pyrite-containing material and forming a pyrite-containing concentrate.

9. The method according to claim 1, further comprising the step of using the inert flow as a water source in a treatment plant for recovering the metal from the metal sulfide-containing material.

10. The method according to claim 1, wherein the metal is copper and the metal sulfide-containing material is a copper sulfide mineral.

11. The method according to claim 10, wherein the pyrite is 1 to 10% by weight of the total mass of the copper sulfide-containing material and the pyrite-containing material.

12. The method according to claim 1, further comprising the step of mixing the metal sulfide-containing material and the pyrite-containing material prior to the leaching step (b).

13. The aforementioned leaching step (b) is, i. A step of agglomerating pyrite-containing material and metal sulfide-containing material to form aggregates, ii. A step of depositing and leaching metal from the aggregate to generate a metal-containing leached liquid in a solution, iii. A step of recovering metal from the leached noble liquid, The method according to claim 12, including the method described in claim 12.

14. A deposition leaching method for mined materials containing copper, nickel, zinc, or cobalt in a metal sulfide-containing material, (a) (i) pyrite-containing material produced from pyrite-containing tailings from a tailings dam or ore processing plant, and (ii) mined material, the step of leaching the deposit of aggregates produced from the material using an acidic leachate and microorganisms, wherein the pyrite in the pyrite-containing material generates acid and heat to facilitate the leaching of copper, nickel, zinc, or cobalt from the mined material, and the microorganisms oxidize ferrous to ferric, (b) A step of collecting a leachate containing copper, nickel, zinc, or cobalt in a solution from the deposit, A method characterized by the following.

15. A deposition leaching operation for leaching copper, nickel, zinc, or cobalt from metal sulfide-containing materials in mined material, (a) (i) a process of forming a deposit of pyrite-containing material generated from pyrite-containing tailings from a tailings dam or ore processing plant, and (ii) a deposit of aggregates generated from the mined material, (b) (i) supplying the deposit with acidic leachate and microorganisms so that the acidic leachate flows downward through the deposit and leaches the copper, nickel, zinc, or cobalt from the mined material; (ii) collecting the leachate containing the copper, nickel, zinc, or cobalt in solution from the deposit, and operating a system in which pyrite generates acid and heat in the deposit to facilitate the leaching of copper, nickel, zinc, or cobalt from the mined material, and the microorganisms oxidize ferrous to ferric; Sedimentation and leaching operations, including those mentioned above.

16. The deposition and leaching operation according to claim 15, wherein pyrite is present in an amount of 1 to 10% by weight of the total mass of the aggregate.

17. A flotation circuit for an ore processing plant for metal sulfide-containing materials, (a) A pulverizer feed flotation circuit for generating tailings and concentrate from a pulverizer feed, wherein the tailings include a metal sulfide-containing material slurry, and the pulverizer feed flotation circuit (b) A pyrite flotation circuit for generating pyrite concentrate and tailings, comprising a pyrite flotation circuit configured to process the pyrite concentrate in accordance with the method for processing pyrite-containing slurry described in any one of claims 1 to 13, Flotation circuit.

18. The aforementioned crusher supply flotation circuit includes a coarse separator / capture cell and a bulk cleaner cell, and the coarse separator / capture cell and the bulk cleaner cell are (i) The coarse sorter / capture cell processes the crusher feed and generates a first tailings stream and a concentrate stream, (ii) The flotation circuit according to claim 17, wherein the bulk cleaner cell is configured to process the concentrate flow to generate a second tailings flow and another concentrate flow, then to transfer the other concentrate flow for further processing and to transfer the second tailings flow to the pyrite flotation circuit for processing in the pyrite flotation circuit.

Images